Why Drink Water? The Health Benefits of H2O

By Jenna Birch

You keep it in the bottle next to your desk and tote it with you to the gym. It’s cool and refreshing, but common and old-school. You probably don’t think much about water. And although it’s not a flavorful sports drink or a trendy beverage like coconut water, H20 still packs a little punch of magic.

According to a new study of 18,300 American adults published in the Journal of Human Nutrition and Dietetics, researchers linked increased water intake to a slew of dietary benefits. Those who bumped their H20 consumption by one, two or three glasses per day ate fewer calories, as well as less saturated fat, sodium, and sugar.

Deena Adimoolam, MD, an assistant professor of Diabetes, Endocrinology, and Bone Disease at the Icahn School of Medicine at Mount Sinai, says drinking water tricks your stomach into thinking it’s full. “The more full you feel, the less likely you are to eat more food,” she says, noting the effect is especially true of unhealthy food that many tend to eat as extra snacks and desserts.

While creating the illusion of fullness can impact your waistline in a super-positive way, water also does a whole lot more for your body. Here are a few fun-fact vital stats about why water is such an all-star player in your routine.

Water Provides Balance to the Body

The magic of water is in the breakdown. H2O is two hydrogen atoms and one oxygen atom. “All our organs and individual cells are composed of water,” says Adimoolam. “The breakdown products of water, hydrogen and oxygen, are vital for our body’s homeostasis, or state of equilibrium.”

If you don’t get enough water, your organs aren’t going to function properly. Enough blood volume won’t be circulating throughout your body. “This is necessary for providing oxygen and nutrients to all our organs in order to keep them healthy and functioning,” says Adimoolam. “If the kidneys, for instance, aren’t functioning properly, then there will be an issue with clearing out toxins, like urea, from the body.”

If You’re Peeing a Lot, that’s a Good Thing

When you’re dehydrated, your organs and cells aren’t getting enough nutrients. Your skin might lack luster, and you might feel low on energy. “Water is important for all cells of the body, including the skin, which has a very high rate of cell turnover.”

So, tipping back eight glasses of water throughout the day (or more) is a good idea. The body will use what it needs, and any excess water will be urinated out. “Our body is always looking to be in a balanced state,” says Adimoolam. “So it will take the water that it needs for normal cell functioning, and urinate the rest out.” That’s right: it’s okay if you’re taking extra trips to the restroom. That just means you’re definitely hydrated.

Dehydration is a Real Doozy

With summer coming up, it’s important to understand what happens when you don’t drink enough water. “There is a decrease in circulating blood volume, and this leads to a decrease in blood pressure,” says Adimoolam. “You might notice symptoms like lightheadedness or dizziness, especially when changing positions from lying down to standing, which are directly due to a decrease in blood volume.

Now, here’s the thing: Individual cells depend on this circulating blood volume for oxygen and nutrients, too. Without water, these cells can’t function properly—which can impact each and every organ system. “When the kidney isn’t getting enough blood, you develop early kidney failure, which ultimately can cause increased toxins and minerals to build up in the body, like urea and calcium,” Adimoolam says. FYI, a major cause of kidney stones is prolonged dehydration. “Water is also very important for our body’s balance of certain electrolytes like sodium,” says Adimoolam. “Severe dehydration can lead to very low levels of sodium, which can be life-threatening if untreated.”

Of course, these effects arising from a lack of H2O are extreme—but the only way to feel your best, feed your organs, and power your body is to drink enough water. Roughly eight glasses should do the trick—but to be super-specific, tip back between a half-ounce to a full ounce of water for every pound you carry, depending on your level of activity and how much you sweat. (So, if you’re 150 pounds, somewhere between 75 to 150 ounces is perfect.)

This article is not intended to substitute for informed medical advice. You should not use this information to diagnose or treat a health problem or condition. Always check with your doctor before changing your diet, altering your sleep habits, taking supplements, or starting a new fitness routine.

Jenna Birch

Jenna Birch is a health and lifestyle journalist. She has written for web and print outlets like Cosmopolitan, O, Psychology Today, SELF, Women’s Health and Men’s Health, among others. She is a relationship columnist for Yahoo, and author of The Love Gap (January 2018, Grand Central Life & Style), a science-backed guide for modern women navigating today’s complicated dating landscape. A University of Michigan alum, Jenna still resides in Ann Arbor, MI.